What does ADSL refer to?
Short for asymmetric digital subscriber line, ADSL is a type of broadband communications technology used for connecting to the Internet. ADSL allows more data to be sent over existing copper telephone lines, called POTS, when compared to traditional modem lines. A special filter, called a microfilter is installed on a your telephone line to allow both ADSL and regular telephone services to be used at the same time. ADSL requires a special ADSL modem and subscribers must be in close in geographical locations to the provider's central office to receive ADSL service. Typically this distance is within a radius of 2 to 2.5 miles. ADSL supports data rates of from 1.5 to 9 Mbps when receiving data (known as the downstream rate) and from 16 to 640 Kbps when sending data (known as the upstream rate). Information from Webopedia

How Does Satellite Work for Internet Users?
How do you access the Internet other than dial-up if you live too far from a phone company office for DSL users area and there is no cable TV in your area Satellite Internet access may be worth considering. It's ideal for rural Internet users who want broadband access. Satellite Internet does not use telephone lines or cable systems, but instead uses a satellite dish for two-way (upload and download) data communications. Upload speed is about one-tenth of the 500 kbps download speed. Cable and DSL have higher download speeds, but satellite systems are about 10 times faster than a normal modem.

What is a Mobile Hotspot?
Mobile hotspots (a.k.a. portable hotspot or portable hot spot) are portable devices or features on smartphones that provide wireless Internet access on many devices (your laptop, smartphone, MP3 player, tablet, portable gaming device, etc.).
Like USB modems from wireless carriers, mobile hotspots typically use mobile broadband service from cellular providers for 3G or 4G Internet access. Unlike USB sticks, though, mobile hotspots allow multiple devices to connect at the same time. Mobile Hotspots can be dearer to run.
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